Bob Norman asked,
"what is the advantage (in terms of insurance) of
getting your camper classified as a motor home?
if it is cheaper, why is this so?"

 Let me take a stab at that one since I've had some
motorhomes and subscribed to periodicals associated with
them.  Probably the main thing is that as a class,
motorhomes in the US get driven on average about 3,500 miles
per year!   I know that sounds pretty low, but on the basis
of large numbers, and that's what insurance companies use in
forming their rate tables, they don't get involved in many
accidents.  This may be largely due to the miles they see,
but also, consider the KINDS of miles they see.  The
percentage of highway miles where accidents per mile is
lower than in stop and go city traffic, is probably higher
for motorhomes than cars.  It's my expectation that the
damage per claim may actually be higher for motorhomes than
cars, but they don't get into many accidents.  But I'm not
even sure about the cost per incident.  I've had some iron
that could total out some common small cars and you'd
probably have to do little more than pick up the spilled
brownies and hose off the front bumper afterward.
John